Extract code for error messages for better reusability

+ Create function for generating permission errors

src/Controllers/admin.controller.ts

@@ -1,31 +1,37 @@
 import prisma from "../lib/prisma";
 import { Request, Response } from "express";
+import { AdminLevel } from "@prisma/client";
+
+const AUTH_ERROR = {
+  type: "failure",
+  payload: {
+    message: "The server was not able to validate your credentials; Please try again later",
+  },
+};
+
+const createInsufficientPermissionsError = (required: AdminLevel = "ELEVATED") => ({
+  type: "error",
+  payload: {
+    message: "You do not have sufficient permissions to use this feature",
+    required_level: required,
+  },
+  _links: [
+    {
+      rel: "authentication",
+      href: "/api/authentication",
+      type: "POST",
+    },
+  ],
+});
 
 // requires: auth(elevated)
 export const getAllAdmins = async (req: Request, res: Response) => {
   if (!req.auth?.isAuthenticated) {
-    return res.status(500).json({
-      type: "failure",
-      payload: {
-        message: "The server was not able to validate your credentials; Please try again later",
-      },
-    });
+    return res.status(500).json(AUTH_ERROR);
   }
 
   if (req.auth.permission_level !== "ELEVATED") {
-    return res.status(403).json({
-      type: "error",
-      payload: {
-        message: "You do not have sufficient permissions to use this feature",
-      },
-      _links: [
-        {
-          rel: "authentication",
-          href: "/api/authentication",
-          type: "POST",
-        },
-      ],
-    });
+    return res.status(403).json(createInsufficientPermissionsError());
   }
 
   // TODO: Add exception handling